Abstract: A fluent ceramic material is provided under pressure to a plurality of piston and cylinder devices for the purpose of dispensing drops to form balls of ceramic material. The piston and cylinder devices are each provided with a nozzle positioned above a droplet catch basin containing an aqueous gelatinizing solution. A cam mechanism controls the stroke of a piston in each cylinder so that a specific amount of the fluent ceramic material from the storage tank is dispensed in drops from the nozzles into the droplet catch basin. The use of the cam mechanism ensures the dispensing of a specific amount of material from the nozzle corresponding to a desired diameter of the resulting ceramic material ball. The desired diameter can be easily changed by appropriately changing a cam disk of the cam mechanism. The rate of production can be appropriately increased or decreased by increasing or decreasing the cyclic rate of the pistons.

Abstract: A measuring probe for a measuring head to detect the oxygen activity of metal melts has a reference substance of known oxygen activity, which upon submersion into the metal melt is separated from the metal melt by means of a refractory solid electrolyte that conducts electrons reliably and conducts primarily oxygen at higher temperatures and which permits the measurement of the electromotive force between the reference substance and a bath contact which makes contact with the metal melt. The surface of the solid electrolyte is subjected to a surface cleaning treatment, primarily by means of etching.

Abstract: A liquid transfer ball formed from sintered zirconium oxide particles which exhibits utility as the ball element of a ball pen writing instrument to transfer ink from an ink reservoir to a writing surface such as paper. The ball exhibits a porosity of less than 8% by volume and is immune to corrosive action of inks.

Abstract: The addition of zirconium hydroxide to zirconia ceramic material in amounts >11 wt. % of the ceramic batch material plus hydroxide results in the development of a porous sintered zirconia-containing body for use as catalyst substrates and insulating refractories.

Abstract: Mature zirconia ceramic compositions stabilized in the monoclinic and tetragonal structure with 0.1-5% ZnO and as little as 0.5% of a primary stabilizer selected from MgO, Y.sub.2 O.sub.3 or combinations thereof. Compacted ceramic compositions are fired and matured at temperatures below the volatilization point of ZnO and in the range of 2750.degree.-2950.degree. F.Zirconia is conventionally batched with magnesia, yttria or mixtures thereof, with or without other known stabilizers including ceria and calcia, together with up to about 5% ZnO and then compacted and sintered at a temperature which retains at least 0.1% ZnO in the fired body. Conventional cooling is prescribed. Subsequent thermal cycling of the fired body between 400.degree. and 2500.degree. F. reveals a stable body with no degradation in strength. Magnesia stabilized compositions show no signs of early destabilization on thermal cycling and may even show increasing room temperature strength as cycling progresses.